/*
 * Created on Feb 9, 2005
 * Created by Alon Rohter
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

package org.gudy.azureus2.pluginsimpl.local.network;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.security.spec.AlgorithmParameterSpec;

import javax.crypto.spec.SecretKeySpec;

import org.gudy.azureus2.plugins.messaging.MessageStreamDecoder;
import org.gudy.azureus2.plugins.messaging.MessageStreamEncoder;
import org.gudy.azureus2.plugins.network.Connection;
import org.gudy.azureus2.plugins.network.ConnectionManager;
import org.gudy.azureus2.plugins.network.RateLimiter;
import org.gudy.azureus2.plugins.network.Transport;
import org.gudy.azureus2.plugins.network.TransportCipher;
import org.gudy.azureus2.plugins.network.TransportException;
import org.gudy.azureus2.plugins.network.TransportFilter;
import org.gudy.azureus2.pluginsimpl.local.messaging.MessageStreamDecoderAdapter;
import org.gudy.azureus2.pluginsimpl.local.messaging.MessageStreamEncoderAdapter;

import com.aelitis.azureus.core.AzureusCore;
import com.aelitis.azureus.core.networkmanager.ConnectionEndpoint;
import com.aelitis.azureus.core.networkmanager.NetworkManager;
import com.aelitis.azureus.core.networkmanager.ProtocolEndpoint;
import com.aelitis.azureus.core.networkmanager.ProtocolEndpointFactory;
import com.aelitis.azureus.core.networkmanager.impl.TransportHelper;
import com.aelitis.azureus.core.networkmanager.impl.TransportHelperFilter;
import com.aelitis.azureus.core.networkmanager.impl.TransportHelperFilterStreamCipher;
import com.aelitis.azureus.core.networkmanager.impl.tcp.TCPTransportHelper;
import com.aelitis.azureus.core.networkmanager.impl.tcp.TCPTransportImpl;
import com.aelitis.azureus.core.networkmanager.impl.udp.UDPNetworkManager;
import com.aelitis.azureus.core.networkmanager.impl.udp.UDPTransport;
import com.aelitis.azureus.core.networkmanager.impl.udp.UDPTransportHelper;

/**
 *
 */
public class ConnectionManagerImpl implements ConnectionManager {

    private static ConnectionManagerImpl instance;

    public static synchronized ConnectionManagerImpl getSingleton(AzureusCore core) {
        if (instance == null) {

            instance = new ConnectionManagerImpl(core);
        }

        return (instance);
    }

    private AzureusCore azureus_core;

    private ConnectionManagerImpl(AzureusCore _core) {

        azureus_core = _core;
    }

    public Connection createConnection(InetSocketAddress remote_address, MessageStreamEncoder encoder, MessageStreamDecoder decoder) {
        ConnectionEndpoint connection_endpoint = new ConnectionEndpoint(remote_address);

        connection_endpoint.addProtocol(ProtocolEndpointFactory.createEndpoint(ProtocolEndpoint.PROTOCOL_TCP, remote_address));

        com.aelitis.azureus.core.networkmanager.NetworkConnection core_conn =
                NetworkManager.getSingleton().createConnection(connection_endpoint, new MessageStreamEncoderAdapter(encoder),
                        new MessageStreamDecoderAdapter(decoder), false, false, null);

        return new ConnectionImpl(core_conn, false);
    }

    public int getNATStatus() {
        return (azureus_core.getGlobalManager().getNATStatus());
    }

    public TransportCipher createTransportCipher(String algorithm, int mode, SecretKeySpec key_spec, AlgorithmParameterSpec params)
            throws TransportException {
        try {
            com.aelitis.azureus.core.networkmanager.impl.TransportCipher cipher =
                    new com.aelitis.azureus.core.networkmanager.impl.TransportCipher(algorithm, mode, key_spec, params);
            return new TransportCipherImpl(cipher);
        } catch (Exception e) {
            throw new TransportException(e);
        }
    }

    public TransportFilter createTransportFilter(Connection connection, TransportCipher read_cipher, TransportCipher write_cipher)
            throws TransportException {
        Transport transport = connection.getTransport();
        if (transport == null) {
            throw (new TransportException("no transport available"));
        }
        com.aelitis.azureus.core.networkmanager.Transport core_transport;
        try {
            core_transport = ((TransportImpl) transport).coreTransport();
        } catch (IOException e) {
            throw new TransportException(e);
        }

        TransportHelper helper;

        if (core_transport instanceof TCPTransportImpl) {
            TransportHelperFilter hfilter = ((TCPTransportImpl) core_transport).getFilter();
            if (hfilter != null) {
                helper = hfilter.getHelper();
            } else {
                helper = new TCPTransportHelper(((TCPTransportImpl) (core_transport)).getSocketChannel());
            }
        } else if (core_transport instanceof UDPTransport) {
            TransportHelperFilter hfilter = ((UDPTransport) core_transport).getFilter();
            if (hfilter != null) {
                helper = hfilter.getHelper();
            } else {
                helper = ((UDPTransport) core_transport).getFilter().getHelper();
                InetSocketAddress addr = core_transport.getTransportEndpoint().getProtocolEndpoint().getConnectionEndpoint().getNotionalAddress();
                if (!connection.isIncoming()) {
                    try {
                        helper =
                                new UDPTransportHelper(UDPNetworkManager.getSingleton().getConnectionManager(), addr, (UDPTransport) core_transport);
                    } catch (IOException ioe) {
                        throw new TransportException(ioe);
                    }
                } else {
                    /**
                     * Not sure how I can grab the UDPConnection object to pass to the incoming connection constructor. The only time I can figure out
                     * where we can link up the UDPConnection object is in UDPConnectionManager.accept - we have a transport object and we construct a
                     * UDPConnection object, so we could link them there - but I don't know if we really should associate the UDP connection with the
                     * transport (might breaks encapsulation).
                     */
                    // helper = new UDPTransportHelper(UDPNetworkManager.getSingleton().getConnectionManager(), addr, (UDPTransport)core_transport);
                    throw new TransportException("udp incoming transport type not supported - " + core_transport);
                }
            }
        } else {
            throw new TransportException("transport type not supported - " + core_transport);
        }

        TransportHelperFilterStreamCipher core_filter =
                new TransportHelperFilterStreamCipher(helper, ((TransportCipherImpl) read_cipher).cipher,
                        ((TransportCipherImpl) write_cipher).cipher);
        return new TransportFilterImpl(core_filter);
    }

    public RateLimiter createRateLimiter(String name, int bps) {
        return (new PluginRateLimiter(name, bps));

    }

    public class PluginRateLimiter implements RateLimiter {
        private String name;
        private int rate;

        private long total;

        private PluginRateLimiter(String _name, int _bps) {
            name = _name;
            rate = _bps;
        }

        public String getName() {
            return (name);
        }

        public int getRateLimitBytesPerSecond() {
            return (rate);
        }

        public void setRateLimitBytesPerSecond(int bytes_per_second) {
            rate = bytes_per_second;
        }

        public long getRateLimitTotalByteCount() {
            return (total);
        }

        public void updateBytesUsed(int used) {
            total += used;
        }
    }
}
